(1) Field of the Invention
The invention relates to an aircraft with a jettison mechanism.
(2) Description of Related Art
After an accident it is important for all occupants of an aircraft to be able to leave the aircraft quickly. Due to deformation of the airframe as a consequence of the accident the doors may be jammed and it may not be possible to open the doors in a normal way to exit the occupants.
A large exit from the aircraft can be achieved by jettisoning the door from the aircraft by severing all connections of the door to the airframe. A large exit is particularly advantageous if elements, such as backrests of seats project into windows to be used as emergency exits, thus reducing the available cross section for egress by such windows emergency exits.
Door lock mechanisms, e.g. a door lock mechanism of a door of an aircraft, are so arranged, that when the door arm of said door lock mechanism is disconnected, the door will not separate as long as the door lock mechanism is closed. If the door is jettisoned with the door lock mechanism closed the door can be blocked against the fuselage. Therefore the design has to ensure that the jettisoning and unlocking of the door has to be done at the same time.
The document U.S. Pat. No. 3,131,892 describes a door latch assembly for aircraft and helicopters. A closure member for an access opening is secured in completely closed and open positions, but also in a variety of intermediate position. The closure member may be completely removed or jettisoned. When in a generally horizontal position, a cam follower unit makes the door being constrained against reciprocate opening/closing movement. Into another position it effects relative movement between the various sections of a carrier assembly and the unit in the opposite directions, thereby releasing the carrier assembly from frictional engagement with walls of a channel. This permits the door to be reciprocated along the fuselage between. When it is desired to remove the door for jettisoning, a first handle is displaced beyond a limit defined by an abutment element, by rotating a stop lever, distinct and distant from the handle, to remove the abutment element from the path of the handle. Cam followers are completely withdrawn from respective cam slots so that the door is free to fall, since the only forces active on the door which tend to prevent such fall are imparted thereto through an interconnection of the assembly and unit now disengaged.
The document US 2012/085865 describes a door assembly for a helicopter. The door assembly has a post; a door fitted to the post by a first and a second hinge, so as to rotate about a hinge axis to open and close a door opening. An emergency release device has a release handle, and a stem which extends through the post along a release axis substantially perpendicular to the hinge axis, rotates axially, in response to operation of the release handle, from a first to a second angular position to detach the door from the post, and is fixed at one axial end to the first hinge; the release handle being connected to the stem to rotate together with the stem about its release axis.
The document U.S. Pat. No. 6,341,748 discloses an emergency exit system for use primarily in a helicopter or other aircraft. Said emergency exit system includes a panel closing an opening in the fuselage of the aircraft, a plurality of latches for releasably securing the panel in the opening; a release mechanism including slides on each side of the opening for retracting the latches to release the panel; a drive for operating the slides, a drive latch for releasably locking the drive in a cocked condition; and a plurality of principal grab bars strategically located in notches adjacent to the opening and connected to the drive by cables, whereby actuation of any one of the grab bars causes simultaneous release of all of the latches so that the panel can be jettisoned.
The document U.S. Pat. No. 6,427,383 discloses an emergency exit system for use on a helicopter or other aircraft. Said emergency exit system includes a frame defining an opening for receiving a panel to close the opening; a plurality of latches for releasably securing the panel in the opening; a plurality of release mechanisms; a cable extending around at least a major portion of the frame for releasing the panel; and a plurality of actuators strategically located around the opening and connected to the cable, whereby actuation of any one of the actuators causes simultaneous release of all of the latches so that the panel can be jettisoned.
The document EP 0935556 discloses an emergency egress system for facilitating emergency egress of passengers/crewmembers from an aircraft. Said egress system includes an egress panel, a panel frame disposed about the egress panel and a weather strip defining back-to-back channels for accepting the peripheral edges of the egress panel and the panel frame. Furthermore, the emergency egress system includes a plurality of retention devices disposed about the periphery of the egress panel for laterally retaining the egress panel with respect to the panel frame in a normal operating mode, a cam means operative to forcibly urge a portion of the weather strip out of engagement with one of the peripheral edges and an actuation means operative to sequentially disengage at least one of the retention devices and actuate the cam means in an emergency operating mode. Following actuation, a passenger/crewmember may detach the egress panel from the panel frame.
The U.S. Pat. No. 3,851,845 relates to an aperture closure device incorporating a quick release mechanism adapted for incorporation in an aircraft door to effect jettisoning of the door in an emergency. The device includes a plurality of separable hinges operated by a single lever from within the aircraft which can further incorporate means for simultaneously releasing the normal door closing mechanism, thereby effecting complete release of the door by operation of the single lever incorporating a quick release mechanism.